class Test::Unit::UI::TestRunnerMediator

def run_suite(result=nil, run_context=nil)

https://github.com/test-unit/test-unit/issues/38
See GitHub#38

should use runner change public API.
NetBeans should not use monkey patching. NetBeans
Just for backward compatibility for NetBeans. 
def run_suite(result=nil, run_context=nil)
  if result.nil?
    run
  else
    @suite.run(result, run_context: run_context) do |channel, value|
      notify_listeners(channel, value)
    end
  end
end